Magic: The Gathering nearly introduced a playable scratch-off card back in 1999.
In 1998, Wizards of the Coast released Unglued - a non-legal set of cards making fun of pop culture as well as the game of Magic itself, and creating all sorts of wacky or ironic types of cards. It started selling well, and so Mark Rosewater began work on a follow-up set for 1999 - Unglued 2: The Obligatory Sequel. Cards were designed, art was drawn, and things seemed great.
That is until it was found out that WotC did another Fallen Empires and way overprinted, meaning they were actually taking a loss on them. The sequel was put on hiatus and eventually never released. Some of the cards and art later came out, but some, like the vegetable creature race cards, never were released. Eventually, an un-set returned in 2004 with Unhinged, but a lot of Unglued 2 remained unused.
While there were some crazy cards set to be in Unglued 2, perhaps the craziest was some Magic never tried before and haven't tried since - lotto-styled scratch-off cards. The idea was that each pack would get one, with each time you cast it, you scratch off one of the lines. However there were a lot of problems, both in cost and playability.
As Mark Rosewater put it:
"There's out of the box and then there's OUT OF THE BOX. Unglued 2 was doing a lot of wacky things but probably none wackier than this. Hot Picks was one of our scratch-off cards. You heard me—scratch off. The idea was that we'd have a sheet of scratch-off cards so you'd get one in every booster pack. Each card would have three scratch off lines on it and each time you cast it you would scratch one line off.
The problem we ran into and the reason we ended up not using these in Unhinged (well, that and some logistical issues) was that we couldn't get past the problem of players knowing what was coming. We tried to hide it a bit by having numerous versions, but in the end we could hide the second scratch off some of the time and we could never hide the third scratch off if you were aware of what cards were printed.
The theme of these cards was we had the art look like scratch off lottery tickets. There were two in each color."
While it would have been a wild card to have, concerns were raised well before the cancellation of Unglued 2. While some cards with removable parts were later introduced, such as a peelible land card, scratch off cards have never been really mentioned again since 1998.
